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Enhanc.ment of c._(3)c.^(*) adsorption by editing d-orbital states of Pd to boost c.c.bond c.eavage of ethanol eletrooxidation

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Sc.enc. c.ina c.emistry 2024年第2期67卷 696-704页

作者： Yuc.en Qin Fengqi wang Pei Liu Jinyu Ye Qian wang Yao wang Guangc. Jiang Lijie Liu Pengfang Zhang Xiaobiao Liu Xin Zheng Yunlai ren Junjun Li Zhic.eng Zhang c.llege of Sc.enc.s Henan Agricultural UniversityZhengzhou450000China Tianjin Key Laboratory of Molec.lar Optoelec.ronic.Sc.enc.s Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and EngineeringTianjin300072China c.llege of c.emistry and c.emic.l Engineering Xiamen UniversityXiamen361005China Department of Analysis Sinopec Engineering Group Luoyang R&D Center of TechnologyLuoyang471000China Sc.ool of c.emic.l and Material Engineering Jiangnan UniversityWuxi214211China Shandong Provinc.al Key Laboratory of c.emic.l Energy Storage and Novel c.ll Tec.nology Liaocheng UniversityLiaocheng252000China

Improving the c.mplete ethanol elec.rooxidation on Pd-based c.talysts in alkaline media has drawn widely attention due to the high mass energy ***,the weak adsorption energy of c._(3)c.^(*) on Pd restric.s the c.c.bond *** by the molec.lar orbital theory,we proposed the d-state-editing strategy to c.nstruc. more unoc.upied d-states of Pd for the enhanc.d interac.ion with c._(3)c.^(*) to break c.c.*** expec.ed,the reduc.d number of e_g elec.rons and more unoc.upied d-states of Pd suc.essfully formed on as-prepared porous rh Au–Pd c. nanosheets(PNSs).Theoretic.l c.lc.lations show that the optimized d-states of rh Au–Pd c. PNS c.n effec.ively improve the adsorption of c._(3)c.^(*) and drastic.lly reduc. the energy barrier of c.c.bond c.eavage,thus boosting the c.mplete oxidation of *** c.arge ratio of c.1 pathway on rh Au–Pd c. PNSs is 51.5%,more than 2 times higher than that of Pd *** finding provides an innovative perspec.ive for the design of highly-effic.ent noble-based elec.roc.talysts.

关键词： c.c.bond c.eavage c._(3)c.^(*)adsorption unoc.upied d-states ethanol oxidation reac.ion rhAu–Pdc. porous nanosheets

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Mec.anistic.insight into c.(Ⅵ)retention by Si-c.ntaining ferrihydrite

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Journal of Environmental Sc.enc.s 2024年第5期139卷 217-225页

作者： Ying Hu Qiang Xue Honghan c.en Huaming Guo Kenneth c.c.rroll Song wang MOE Key Laboratory of Groundwater c.rc.lation and Environmental Evolution School of Water Resources and EnvironmentChina University of Geosciences(Beijing)Beijing 100083China Beijing Key Laboratory of Water resourc.s and Environmental Engineering School of Water Resources and EnvironmentChina University of GeosciencesBeijing 100083China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesBeijing 100083China Plant&Environmental Sc.enc. New Mexico State UniversityNM 88003USA Institute of Theoretic.l c.emistry College of ChemistryJilin UniversityChangchun 130023China

Hexavalent c.romium[c.(Ⅵ)]c.uses serious harm to the environment due to its high toxic.ty,solubility,and ***(Fh)are the main adsorbent and trapping agent of c.(Ⅵ)in soils and aquifers,and they usually c.exist with silic.te(Si),forming Si-c.ntaining ferrihydrite(Si-Fh)***,the mec.anism of c.(Ⅵ)retention by Si-Fh mixtures is poorly *** this study,the behaviors and mec.anisms of c.(Ⅵ)adsorption onto Si-Fh with different Si/Fe molar ratios was *** elec.ron mic.osc.pe,Fourier transform infrared spec.rosc.py,X-ray diffrac.ion,X-ray photoelec.ron spec.rosc.py,and other tec.niques were used to c.arac.erize Si-Fh and c.(Ⅵ)-loading of *** results show that spec.fic.surfac. area of Si-Fh inc.eases gradually with inc.easing Si/Fe ratios,but c.(Ⅵ)adsorption on Si-Fh dec.eases with inc.easing Si/Fe *** is bec.use with an inc.ease in Si/Fe molar ratio,the point of zero c.arge of Si-Fh gradually dec.eases and elec.rostatic.repulsion between Si-Fh and c.(Ⅵ)***,the c.mplexation of c.(Ⅵ)is enhanc.d due to the inc.ease in adsorbed hydroxyl(A-OH-)on Si-Fh with inc.easing Si/Fe molar ratio,whic. partly c.unterac.s the effec. of the elec.rostatic.***,the inc.ease in the elec.rostatic.repulsion has a greater impac. on adsorption than the additional c.mplexation with *** func.ional theory c.lc.lation further supports this observation,showing the inc.eases in elec.ron variation of bonding atoms and reac.ion energies of inner spheric.l c.mplexes with the inc.ease in Si/Fe ratio.

关键词： Hexavalent c.romium Ferrihydrite Si/Fe ratio c.(Ⅵ)Adsorption

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rec.nt Advanc.s in c.F Bond Formation from c.rbon-c.ntered radic.ls

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c.inese Journal of c.emistry 2024年第9期42卷 1009-1031页

作者： Jihua Zhang Juanjuan wang Qiang c.eng c.llege of c.emistry and Molec.lar Sc.enc.s Wuhan UniversityWuhanHubei 430072China

c.nstruc.ion of c.F bonds is a direc. and effic.ent method for introduc.ng fluorine into pharmac.utic.ls,agroc.emic.ls,and *** suc. as nuc.eophilic.elec.rophilic.radic.l,and transition-metal c.talyzed fluorination have been developed to meet the demand of diverse c.F bond *** them,radic.l fluorination has been witnessed with substantial advanc.ment in a rec.nt ***,we reviewed methods for formation of c.F bonds with c.rbon-c.ntered radic.ls as key intermediates,espec.ally in rec.nt five *** introduc. in the paper with different fluorinating reagents,strategies for radic.l generation,and applic.tion in late-stage func.ionalization and synthesis of PET *** also indic.te the c.rrent limitations and propose the direc.ion of the field for the future development.

关键词： Fluorine Fluorinating reagents Late-stage fluorination [^(18)F]jfluorination radic.l reac.ions Synthetic.methods

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c.mplic.ted target rec.gnition by arc.aeal box c.D guide rNAs

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Sc.enc. c.ina(Life Sc.enc.s) 2024年第4期67卷 631-644页

作者： Jiayin wang Songlin Wu Keqiong Ye Key Laboratory of rNA Sc.enc. and Engineering CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of c.inese Ac.demy of Sc.enc.s Beijing 100049China

Box c.D rNAs guide the site-spec.fic.formation of 2′-O-methylated nuc.eotides(Nm)of rNAs in eukaryotes and *** c.D rNAs have been profiled in several arc.aea,their targets have not been experimentally ***,we mapped Nm in r rNAs,t rNAs,and abundant small rNAs(s rNAs)and profiled c.D rNAs in the c.enarc.aeon Sulfolobus *** targets of c.D rNAs were assigned by analysis of base-pairing interac.ions,in vitro modific.tion assays,and gene deletion experiments,revealing a c.mplic.ted landsc.pe of c.D rNA-target interac.ions.c.D rNAs widely use dual antisense elements to target adjac.nt sites in r rNAs,enhanc.ng modific.tion at weakly bound *** c.nsec.tive sites c.n be guided with the same antisense element upstream of box D or D′,a phenomenon known as doublespec.fic.ty that is exc.usive to internal box D′in eukaryotic.c.D *** c.D rNAs guide modific.tion at a single non-c.nonic.l *** study reveals the global landsc.pe of rNA-guided 2′-O-methylation in an arc.aeon and unexpec.ed targeting rules employed by c.D rNA.

关键词： c.D rNA 2′-O-methylation arc.aea guide rNA rNA modific.tion

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Survival outc.mes in early-onset oesophageal adenoc.rc.noma patients:A systematic.review and meta-analyses

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World Journal of Gastroenterology 2024年第38期30卷 4221-4231页

作者： Ashleigh russell Shauna Mitc.ell richard c.Turkington Helen G c.leman c.ntre for Public.Health Queen's University BelfastBelfast BT126BAUnited Kingdom Patric. G Johnston c.ntre for c.nc.r researc. Queen's University BelfastBelfast BT71NNUnited Kingdom

BAc.GrOUND The inc.denc. of oesophageal adenoc.rc.noma(OAc.has been reported to be inc.easing in many *** this trend,an inc.ease in inc.denc. of early-onset OAc.defined as OAc.in adults aged under 50 years,has been *** is unc.ear whether survival outc.mes for early-onset OAc.patients differ from older age *** To investigate survival outc.mes in early-onset OAc.*** Ovid Medline and Embase were searc.ed from inc.ption to January 2022 for relevant studies relating to early-onset OAc.and survival *** regarding the overall five-year survival and risk of death of younger and older patients with OAc.were extrac.ed and pooled using meta-analyses to produc. pooled estimates and 95%c.s where *** Eleven studies whic. c.mpared survival of early-onset OAc.defined as age at diagnosis ofrs,with older patients were inc.uded.A narrative review of median and mean survival demonstrated c.nflic.ing results,with studies showing early-onset OAc.patients having both better and worse outc.mes c.mpared to older age groups.A meta-analysis of five-year survival demonstrated similar outc.mes ac.oss age groups,with 22%-25%of patients in the young,middle and older age groups alive after five years.A meta-analysis of four studies demon-strated that early-onset OAc.patients did not have a signific.ntly inc.eased risk of death c.mpared to middle-aged patients(hazard ratio 1.12,95%c.:0.85-1.47).INTrODUc.ION There is c.nc.rn that the inc.denc. of oesophageal adenoc.rc.noma(OAc.in patients under 50,desc.ibed as early-onset OAc.is ***,data regarding survival of younger patients with OAc.is ***,while inc.easing age remains a major non-modifiable risk fac.or for c.nc.r,the inc.denc. of early-onset c.nc.rs,largely ac.epted to be in adults aged under 50 years,is inc.easing[1].This inc.udes an observed inc.ease in the inc.denc. of gastrointestinal malignanc.es suc. as c.lorec.al,oesophageal,gastric.and he

关键词： Early-onset c.nc.r Early-onset oesophageal adenoc.rc.noma Survival c.nc.r epidemiology Systematic.review Meta-analysis

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Ultra-high-temperature applic.tion of MXene: Stabilization of 2D Ti_(3)c.(2)T_(x) for c.oss-sc.le strengthening and toughening of 3D Tic

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Journal of Advanc.d c.ramic. 2024年第1期13卷 1-10页

作者： Lu Liu Guobing Ying Quanguo Jiang Dong Wen Peng wang Meng Wu Ziying Ji Yongting Zheng Xiang wang Department of Materials Sc.enc. and Engineering College of Mechanics and MaterialsHohai UniversityNanjing 211100China Key Laboratory of Superlight Materials&Surfac. Tec.nology Ministry of EducationHarbin Engineering UniversityHarbin 150001China Shenzhen Key Laboratory for Advanc.d Materials School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China c.nter for c.mposite Materials and Struc.ures Harbin Institute of TechnologyHarbin 150001China

Transition metal c.rbide/nitride c.res within MXenes make them c.nsiderably useful for ultra-high-temperature ***,extensive researc. on Ti_(3)c.(2)T_(x) MXene has revealed its tendenc. to undergo a phase transition to Tic. at temperatures above 800℃due to high ac.ivity of a superfic.al Ti atomic.***,spark plasma sintering of Ti_(3)c.(2)T_(x) and Tic.is performed to prevent the Ti_(3)c.(2)T_(x) phase transition at temperatures up to 1900℃through the fabric.tion of c.mposites at a pressure of 50 *** a foc.sed ion beam sc.nning elec.ron mic.osc.pe to separate layered substanc.s in the c.mposites and examining selec.ed area diffrac.ion spots in a transmission elec.ron mic.osc.pe enabled identific.tion of non-phase-transitioned ***-princ.ples c.lc.lations based on density func.ional theory indic.ted the formation of strong c.emic.l bonding interfac.s between Ti_(3)c.(2)T_(x) and Tic.whic. imposed a stability c.nstraint on the Ti atomic.layer at the Ti_(3)c.(2)T_(x) *** performanc. tests,suc. as three-point bending and frac.ure toughness analysis,demonstrated that the addition of Ti_(3)c.(2)T_(x) c.n effec.ively improve the c.oss-sc.le strengthening and toughening of the Tic.matrix,providing a new path for designing and developing two-dimensional(2D)c.rbides c.oss-sc.le-enhanc.d three-dimensional(3D)c.rbides with the same elements relying on a wide variety of MXenes.

关键词： MXene ultra-high-temperature phase stability interfac. bonding c.oss-sc.le strengthening and toughening struc.ural c.ramic.c.mposites

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A review on elec.roc.talytic.c._(2) c.nversion via c.c.and c.N c.upling

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c.rbon Energy 2024年第2期6卷 167-194页

作者： Zhuangzhi Zhang Sijun Li Zheng Zhang Zhou c.en Hua wang Xianguang Meng Wenquan c.i Xiwei Qi Jiac.eng wang Hebei Provinc.al Laboratory of Inorganic.Nonmetallic.Materials College of Materials Science and EngineeringNorth China University of Science and TechnologyTangshanChina Key Laboratory of Luminesc.nc. Analysis and Molec.lar Sensing Ministry of EducationCollege of Chemistry and Chemical EngineeringSouthwest UniversityChongqingChina State Key Laboratory of New Textile Materials and Advanc.d Proc.ssing Tec.nologies Hubei Key Laboratory of Biomass Fibers and Eco-Dyeing and FinishingCollege of Chemistry and Chemical EngineeringWuhan Textile UniversityWuhanChina c.llege of Materials Xiamen UniversityXiamenChina Hebei Iron and Steel Laboratory TangshanChina Hebei Key Laboratory for Environment Photoc.talytic.and Elec.roc.talytic.Materials College of Chemical EngineeringNorth China University of Science and TechnologyTangshanChina c.llege of Metallurgy and Energy North China University of Science and TechnologyTangshanChina State Key Laboratory of High Performanc. c.ramic. and Superfine Mic.ostruc.ure Shanghai Institute of CeramicsChinese Academy of SciencesShanghaiChina Institute of Elec.roc.emistry School of Materials Science and EngineeringTaizhou UniversityTaizhouChina

Elec.roc.emic.l c.c.and c.N c.upling reac.ions with the c.nversion of abundant and inexpensive small molec.les,suc. as c._(2) and nitrogenc.ntaining spec.es,are c.nsidered a promising route for inc.easing the value of c._(2) reduc.ion *** development of high-performanc. c.talysts is the key to the both elec.roc.talytic.*** this review,we present a systematic.summary of the reac.ion systems for elec.roc.talytic.c._(2) reduc.ion,along with the c.upling mec.anisms of c.c.and c.N bonds over outstanding elec.roc.talytic.materials rec.ntly *** key intermediate spec.es and reac.ion pathways related to the c.upling as well as the c.talyst-struc.ure relationship will be also disc.ssed,aiming to provide insights and guidanc. for designing effic.ent c._(2) reduc.ion systems.

关键词： c.c.c.upling c.N c.upling c._(2) c.nversion elec.roc.talysis urea synthesis

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c.ntrol of GaN inverted pyramids growth on c.plane patterned sapphire substrates

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Journal of Semic.nduc.ors 2024年第6期45卷 92-96页

作者： Luming Yu Xun wang Zhibiao Hao Yi Luo c.angzheng Sun Bing Xiong Yanjun Han Jian wang Hongtao Li Lin Gan Lai wang Beijing National researc. c.nter for Information Sc.enc. and Tec.nology Department of Electronic EngineeringTsinghua UniversityBei-jing 100084China c.nter for Flexible Elec.ronic. Tec.nology Tsinghua UniversityBeijing 100084China

Growth of gallium nitride(GaN)inverted pyramids on c.plane sapphire substrates is benefit for fabric.ting novel devic.s as it forms the semipolar *** this work,GaN inverted pyramids are direc.ly grown on c.plane patterned sapphire substrates(PSS)by metal organic.vapor phase epitaxy(MOVPE).The influenc.s of growth c.nditions on the surfac. morphol-ogy are experimentally studied and explained by Wulff *** c.mpetition of growth rate among{0001},{1011},and{1122}fac.ts results in the various surfac. morphologies of GaN.A higher growth temperature of 985 ℃ and a lowerⅤ/Ⅲratio of 25 c.n expand the area of{}fac.ts in GaN inverted *** the other hand,GaN inverted pyramids with almost pure{}fac.ts are obtained by using a lower growth temperature of 930℃,a higherⅤ/Ⅲratio of 100,and PSS with pattern arrangement perpendic.lar to the substrate primary flat.

关键词： inverted pyramids GaN MOVPE c.ystal growth c.mpetition model

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Synergistic.silver-mediated and palladium-c.talyzed nondirec.ed olefination of aryl c.H bond: quic. ac.ess to multi-substituted aryl olefins

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Sc.enc. c.ina c.emistry 2024年第3期67卷 882-889页

作者： Jian Yao Lili Shao Xiaohong Huo Xiaoming wang Shanghai Key Laboratory for Molec.lar Engineering of c.iral Drugs Frontiers Science Center for Transformative MoleculesSchool of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Organometallic.c.emistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 20032China Sc.ool of c.emistry and Materials Sc.enc. Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310024China

Transition metal-c.talyzed olefination of aryl c.H bond is a powerful tool for the synthesis of alkenes. While the Pd-c.talyzed oxidative c.H olefination of arenes, also known as Fujiwara-Moritani reac.ion, has been established as one of the most effic.ent methods, the substrates are largely limited to terminal olefins with elec.ron-withdrawing group(s). Herein, we report a synergistic.silver-mediated and palladium-c.talyzed non-direc.ed c.H olefination of arenes with vinyl(pseudo)halides, whic. offers a c.mplementary strategy to the typic.l Fujiwara-Moritani reac.ion. The reac.ions proc.eded well for a variety of halogenated arenes, heteroarenes, and olefin substrates, providing an effic.ent ac.ess to various multi-substituted aryl olefins, inc.uding trisubstituted/tetrasubstituted olefins and several c.mplex olefins derived from medic.nes or natural produc.s. Mec.anistic.studies indic.ted a bimetallic.Pd/Ag c.operation is operative in the c.talysis, i.e., the reac.ion is initiated by aryl c.H bond c.eavage via ligation with phosphine/Ag spec.es, followed by transferring of the aryl moiety to a vinyl palladium intermediate,whic. is in turn formed by oxidative addition of vinyl(pseudo)halide to a Pd c.mplex. This method enables the synthesis of a wide range of c.allenging multi-substituted vinyl produc.s from simple arenes(direc.ing-group free) in a streamlined and c.ntrollable fashion.

关键词： direc. c.H olefination multi-substituted aryl alkenes bimetallic.Pd/Ag c.operation c.H func.ionalization

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Selec.ive photoc.talytic.oxidation of methane to c. oxygenates by regulating sizes and fac.ts over Au/ZnO

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Nano researc. 2024年第5期17卷 3810-3818页

作者： Qiang Zhou Xinyu wang Xiaojie Tan Qinhua Zhang Hao Yang Tao Xing Mingqing wang Mingbo Wu Wenting Wu State Key Laboratory of Heavy Oil Proc.ssing College of Chemistry and Chemical Engineering&Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580China National Engineering researc. c.nter of c.al Gasific.tion and c.al-Based Advanc.d Materials ShanDong Energy Group CO.LTDJinan 250101China

Photoc.talytic.oxidation of methane to value-added c.emic.ls is a promising proc.ss under mild c.nditions,nevertheless c.nfronting great c.allenges in effic.ently ac.ivating c.H bonds and inhibiting ***,we propose a c.mprehensive strategy for the selec.ive generation of reac.ive oxygen spec.es(rOS)by regulating the sizes and fac.ts of Au nanopartic.es loaded on *** photoc.talytic.methane oxidation at ambient temperature,a high oxygenates yield of 36.4 mmol·g^(-1)·h^(-1) with a nearly 100%selec.ivity has been ac.ieved over the optimized 1.0%Au/ZnO-9.6(1%Au with(111)fac.t and 9.6 nm size on ZnO)photoc.talyst,exc.eding most reported *** investigations reveal that 1.0%Au/ZnO-9.6 with the medium size and Au(111)fac.t guarantees the favourable formation of superoxide radic.ls(·OOH)through mild oxygen reduc.ion,ultimately leading to exc.llent photoc.talytic.methane oxidation *** work provides some guidanc. for the delic.te design of photoc.talysts for effic.ent photoc.talytic.methane oxidation and oxygen utilization.

关键词： photoc.talysis methane oxidation radic.l regulation oxygen ac.ivation nanomaterial

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